Haemodynamics
Patho of heart failure
Catherine patho heart failure
Valvular heart disease
Pharm of antibiotics
100

Upon physical examination Tommy turns out to have a "Soft, low pitched apical pan-systolic murmur is heard radiating to the axilla." 

What pathological change in the heart is causing this murmur? 

A mitral/tricuspid valve incompetence. 

100

If Tommy's heart is failing to effectively pump blood around the body, why doesn't the heart undergo hyperplasia and increase the number of cardiomyoctes? Why hypertrophy? 

If there is mitotic divisions happening the intrinsic conduction system of the heart finds it too difficult to compensate. 

100

In Tommy's case with his acute heart failure why wouldn't you give a him beta-1 agonist? 

  • An increase in HR leads to an increase oxygen demand on of the heart. 
  • Moreover, an agonist decreases T-P interval which is where passive ventricular filling time occurs, lowering total SV 
  • Would result in ischemia and worsening of symptoms
100

WOW HAP QUESTION WORTH 600 POINTS

How much more likely are indigenous Australians like Tommy to die from RHD? Why are they more likely to suffer from it's long term consequences? 

 20x more likely 

WORST IN THE WORLD 

SOCIAL DETERMINANTS 

  • Poor access to medical care
  • Poverty
  • Housing à overcrowding
  • Dental care
  • Scabies and sores prevention and treatment – health hardware
  • Education
100

A good drug only targets pathogens without damaging human cells. What is this desirable property called?  

Selective toxicity

200

Tommy presents with the following CXR: Patient (indicates pulmonary oedema and cardiomegaly and Kerley B lines) 


What is the difference between effusion and oedema? List 4 places you could find effusion. 

While oedema is fluid in the subcutaneous tissues, effusion is fluid in ‘potential spaces’ as well as subcutaneous tissues. 

Potential spaces are:

  • Pleural cavity
  • Pericardial cavity
  • Peritoneal cavity
  • Synovial cavity


200

The extent of Tommy's heart failure can be measured by a specific blood test. What is it?

B-type natriuretic peptide protein secreted by the ventricles during excessive stretching 

200
Describe an aortic stenosis murmur? When does it occur? 

Crescendo-decrescendo murmur that occurs during systole. 

200

What bacteria causes strep throat and the severe problems related to rheumatic fever including anemia. 

Group A hemolytic streptococci 

200

List the 3 drug classes that inhibit protein synthesis and an example for each. 

TAM (like TIMTAM YUM) 

Tetracyclines - doxycycline 

Aminoglycosides - gentamicin 

Macrolides - erythromycin 

300

List the 5 types of shock and briefly describe them. 

  • Cardiogenic: Heart cannot pump normally --> low CO, low BP
  • Hypovolemic: Loss of plasma volume --> low SV, low CO, low BP
  • Septic: Pathogen in blood causes cytokines and histamines to be released. Systemic vasodilation causes a massive drop in BP
  • Neurogenic: Attributed to disruption of the autonomic pathways within the spinal cord, decreased CO and impacts TPR (vasomotor centre)
  • Anaphylaxis occurs in an individual after re-exposure to an antigen to which that person has produced a specific IgE antibody. Systemic vasodilation. 
300

While Tommy has no history of smoking or alcohol consumption, what is the most common idiopathic toxic cause of dilated cardiomyopathy? 

Alcohol. 1/3 of dilated cases. 

300

What causes the processes in the compensated heart to eventually fail? 

High filling volumes (>150mls) leads to high resistance in ventricules during passive ventricular filling. Any further EDV leads to an loss of the increased contractile strength of cardiomyocytes, as they are overstretched. 

300

Tommy has had rhuematic fever as a child. What is the JONES criteria for rheumatic fever? 

  • Carditis
  • Endocarditis- valvular inflammation and scarring is most imp
  • Myocarditis: acute; may lead to ventricular dilatation
  • Most common cause of death
  • Pericarditis: transient, no long term sequelae, effusions and rub
  • Bacteria increases oncotic pressure in pericardium and draws in more fluid
  • Polyarthritis
  • Usually weight being joints
  • Pain but not very swollen
  • Sydenham Chorea à rapid face and arm movements (3 months in)
  • Erythema marginatum à red rings
  • Subcutaneous nodules à collagen bumps
300

What class of macromolecule synthesis are sulfonamides a part of? What does it inhibit?

Class II - Exploit some difference between human & bug – eg. Vitamin, AA synthesis

Folate synthesis

400

"Tommy has short of breath while at rest, sitting upright, using accessory muscles of respiration, centrally cyanosed, coughing up pink frothy sputum."

What is happening currently in Tommy's lungs for him to have SOB? 


Currently there is back flow of blood from the left ventricle into the pulmonary circuit during systole. This effectively increases the hydro static pressure in the lungs' vasculature and results in fluid deposits into the interstitial fluid - oedema. This oedema reduces the efficiency of gas exchange in the alveoli and leads to SOB. 


400

What is hypertrophic obstructive cardiomyopathy? (HOCM) How is it different to left ventricular hypertrophy?

Hypertrophic cardiomyopathy is generally caused by genetics and is related to an asymmetrical septal width. This obstruction of blood flow can lead to LVH. 

Left ventricular hypertrophy is caused by a plethora of reasons and is characterised by a free left ventricular wall thickness >1.5CM. 

400

What long term processes does the body use to compensate heart failure? 

  • It increases SV by increasing fluid retention to maintain cardiac output: 
  • Decreased glomerular filtration rate
  • Reduced arterial pressure and sympathetic renal   vasoconstriction reduce
  • Activation of the RAAS


400

Tommy suffers from "atrial fibrillation and acute cardiac failure, secondary to rheumatic heart disease (RHD)." What macroscopic and microscopic changes would you expect to see on his mitral valve? 

Macroscopic

Vegetations --> fibrinoid necrosis

Microscopic 

Aschoff body --> fibrinoid necrosis regions with immune cells

Anitschkow cells --> 'caterpillar cells' with oval nuclei 


400

How do beta-lactams work? List two examples. 

BONUS: +400 points How is it different to vancomycin? 

Enzyme called transpeptidase (penicillin binding protein) is needed

Binds to transpeptidase enzyme preventing bacterial wall synthesis

Amoxycillin & cefalexin 

Vancomycin binds to the peptide chains and prevents them from interacting properly with the cell wall cross-linking enzyme.


500

Tommy's "The trans-oesophageal ECHO reveals moderate mitral regurgitation. His left ventricular function is borderline normal with no atrial dilatation."

What pathological (microscopic) changes would you expect to develop in Tommy's lungs if his left ventricle continued to fail?

Congestion in the lungs from left ventricular failure. 

Engorged (dilated) alveolar capillaries (below)

Then ruptures/hemorrhages into alveoli spaces

Thickened septa with fibrosis

Siderophages – heart failure cells 

Macrophages with hemosiderin

Hemosiderin is an iron carrying protein in the blood

500

What is restrictive cardiomyopathy? 

Restrictive filling--> poor EDV and preload either or both ventricles

Normal/near normal ventricular function --> systolic function and wall thickness.

Heart walls are rigid but not thickened 

500

If left untreated Tommy's acute heart failure could results in a myocardial infarction. What are the 4 steps in the recovery of the heart following an MI? 

  • Normal: Increased venous return increase CO (rapid is normal)

  • Immediately after MI 
  • Not enough blood to maintain consciousness
  • Damage to the heart means that right atrial pressure has increased
  • Venous return is the same however the rate of blood pumping is lower
  • Since pumping is lower there is damming in the heart

  • SNS Reflex
  • Baroreceptors within seconds increases the CO to try and compensate
  • Vasodilation, HR, contractility (via Ca2+)
  • Venoconstriction à increases venous filling pressure, push blood towards your heart
  • Frank Stirling law à greater stretch of heart à greater contractility

  • Semi-chronic state
  • Increase BV (fluid retention) increased venous return by kidneys
  • Partial recovery of heart muscle
500

List the 3 layers of heart valves and what they compose of. 

  • Fibrosa --> dense collagenous core (pink à outflow)
  • Spongiosa --> loose CT
  • Ventricularis or atrialis (depending on which chamber it faces) on inflow surface
500

Explain the MOA for quinolones and an example drug. What enzymes are inhibited? 

  • Inhibits DNA gyrase (Topoisomerase II) à normally reduces DNA tension during replication
  • Inhibits topoisomerase IV enzyme  à needed for two interlinked chromosomes to separate
  • Example is ciprofloxacin 
M
e
n
u